henderson



J n- 4, 1956 c. T. HENDERSON FLUID FEED APPARATUS 4 Sheets-Sheet 1 FiledJan. 10, 1950 nuenZ o 7' Ciarkffienderaon.

Jan. 24, 1956 c. T. HENDERSON FLUID FEED APPARATUS 4 Sheets-Sheet 5Filed Jan. 10 1950 fnuenZZr.-- Czar/0Z fine 9190 5954M, W W

United States Patent FLUID FEED APPARATUS Clark T. Henderson, Wheaten,Iii. Application January 10, 1950, Serial No. 137,825 9 Claims. (Cl.210-46) This invention relates to a liquid feed apparatus and moreparticularly to a liquid feed apparatus for adding solutions such assterilizing fluids, coagulants, stabilizing agents or the'like toanother fluid such as a flowing water supply.

Heretofore, the various devices and pumping systems which have beendeveloped and used for the purpose of adding sterilizing fluids, such aschlorine solutions, to the drinking water supply of cities and largetowns have been large, complicated structures and have been so costly asto prohibit their purchase and use by smaller towns and villages.Consequently, thousands upon thousands of such smaller towns andvillages have been unable to afford to their residents a definitely safewater supply. Furthermore, these former feeding devices requiredconstant supervision by operators, and the various parts thereof weresubject to wear and breakage requiring frequent repair and replacementwith the result that the operational maintenance of these devices wasthe source of additional undesirable costs. Other apparatus such as thatused in municipalities or in industry for adding coagulants to waterahead of filtration or for adding stabiliz ing agents to flowing waterhave likewise been subject to the same objections and disadvantages.

Another disadvantage inherent in such prior liquid feed systems hasresulted from the use of valves which were not positive and eflicient intheir operation and involved the use of springs for valve actuation.Such valves were incapable of regular coordinated operation over a longperiod of time and were leaky and slow acting in their opening andclosing operation.

It is, therefore, an object of the present invention to provide animproved form of liquid feed apparatus whereby one additive fluid suchas a chemical solution, may be fed or added in predetermined quantitiesto another fluid, such as water, at a rate proportional to the rate atwhich said other fluid is flowing.

Another object of the present invention is to provide an improved liquidfeed apparatus of the foregoing character which is of simple,inexpensive but efficient construction and has a relatively longoperable life requiring only a minimum of attention during operation andaffording low repair and replacement costs.

Another object is to provide a liquid feed apparatus for feeding anadditive to another fluid under pressure such as a main water supplywhich comprises a pump and a variable pressure mechanism operable bysaid water supply pressure and adapted to effect pump operation byalternately creating a vacuum and an increased pressure on one side ofthe pump.

A further object is to provide a liquid feed apparatus of the foregoingcharacter in which the pump is of the diaphragm type and the valvebetween the pump and the source of additive fluid is also of thediaphragm type, the variable pressure mechanism comprising an ejectoradapted to create alternately a vacuum to open the valve and effect thepump suction stroke and an increased pressure to close the valve andeffect the pumping stroke.

A still further object is to provide an apparatus of the foregoingcharacter in which operation of the variable pressure mechanism iscontrolled by mechanism operably engaged with the water flow meter inthe main fluid supply line.

Another further object is to provide a liquid feed apparatus in whichthe valve for controlling the flow of liquid from the chemical supplytank to the main liquid supply is mechanically actuated for positive,leakproof operation at the desired point of time with respect to thesuction and pumping strokes of the pump.

Other objects and advantages of the present invention will becomeapparent as this description progresses, reference being had to theaccompanying drawings in which:.

Figure 1 is a vertical sectional view of a liquid feed apparatuscomprising one embodiment of the present invention;

Fig. 2 is a horizontal sectional view taken on the line 2-2 in Fig. 1,looking in the direction of the arrows;

Fig. 3 is an end elevational view of the apparatus as viewed from theright in Fig. 1; and

Fig. 4 is a diagrammatic and partial sectional view showing the generalarrangement of the liquid feed apparatus of Figs. 1 and 3, inclusive, inrelation to a source of additive fluid and a main Water supply line andalso showing the wiring diagram of the electrical valve controllingmechanism for the ejector.

The liquid feed apparatus comprising the present invention is shown inFigs. 1 and 3, inclusive, of the drawings, mounted on a base 10 andsecured thereto by means of spaced angle irons 11 and '12. Thereciprocating pump of the apparatus is of the diaphragm type comprisinga power diaphragm 13 and a pumping diaphragm 14, each composed of anysuitable resilient, flexible ma-- terial, such as rubber or the like.The power diaphragm 13, at the left side of the pump as viewed in Fig.l, is annular in form and is clamped at its peripheral edge portionsbetween two complementary concave, circular body portions 16 and 17,these body portions providing an annular chamber 18 in which the powerdiaphragm 13 is operable for movement from left to right and return."

The body portions 16 and 17 are held in assembled clamping position by aplurality of bolts 15 arranged around the marginal portions thereof.Similarly the pumping diaphragm 14, at the right side of the pump, is ofcircular form and is clamped at its peripheral edge portions between avalve block 19 and a body member 20. The valve block 19 and the bodyportion 20 are concave on their opposed sides and together form apumping chamber 21 in which the pumping diaphragm is operable formovement from the left to right and return. The respective body portionsof the pump forming the two chambers 18 and 21 in which the diaphragmsare operable are joined together and rigidly maintained in properlyspaced relation by a plurality of bracing bars 24.

The diaphragms 13 and 14 are each secured on the respective ends of apump rod 26 reciprocably mounted in the body members 17 and 20. Thepower diaphragm 13 is secured on the left end of the pump rod 26- bymeans of a pair of nuts 27 and a pair of washers 28 between which thediaphragm 13 is clamped, the end of the pump rod 26 being threaded as at29 for threaded engagement with the nuts 27. The pump rod 26 is slidablysupported within a bushing 30 threadedly secured in a central opening 31of the body rnember17, the bushing 30 also serving as a stop member andbeing adjustable within the opening 31 in order to vary the length ofthe stroke of the pump rod 26. The length of the stroke is reduced asthe bushing 30 is screwed inwardly or to the left toward the diaphragm13 and is increased as it is screwed outwardly. The stop bushing 30 isretained in properly adjusted position by means of a lock nut 32Patented Jan. 24, 1956' threadedly securedontheouter threaded peripherythereof. Thesbody member 17 is alsoprovided with an unobstructed opening22 extending therethrough to permit the egress and ingress of air as thediaphragm 13 is moved tov the right or back-to the left duringthepumpingand suction strokes.

The pumping diaphragm 14- is secured on the right endof the pump rod 26by means of a screw-33 extend ing through a central aperture of thediaphragm and havingan enlarged flat head 34 for engagement with theright surface'of the diaphragm. The threaded shank of the screw 33isreceived within a threaded bore 36in the right end of the pumprod 26and a tapered clam ingnut 37 and a washer 38-are mounted on the screw 33between the rod 26 and the diaphragm 14 to serve as an enlarged baseagainst which the diaphragm 14 is clamped by the screw head 34. Securedto the right surface of the diaphragm 14- and to the outer surface ofthe screw head 34 isa thin rubber sheet 14a which serves to protect thescrew head 34 from any possible chemical action of the additive fluid.By the foregoing construction, it isevident that upon movement of thepower diaphragm 13 to the right or to the left as viewed in Figs. 1 and4, the pumping diaphragm 14 will correspondingly be moved either to theright or to the left.

The pumping chamber 21 in which the pumping diaphragm- 14 is operable isconnected by a horizontal passage 39 with a valve chamber 40 in which adiaphragm 41 is operablefor limited movement either to the right or tothe left to open or close the port 42 through which the passage 39connects with the valve chamber 49. The valve chamber 40 is formed by ashallow concavity on the right side of thevalve block 19 and by acomplementary opposed concavity of a valve plate 48. The valve diaphragm41 is circular in form and is clamped at its peripheral edge portionsagainst the valve block by the valve plate 48, the body member 20, thediaphragm 14, the valve body 19, the diaphragm 41 and the valve plate 48being secured together as an assembly by bolts 23.

As shown particularly in Fig. 4, a pipe 44 extends downwardly into atank 46 in which is contained a supply of the chemical solution oradditive fluid to be injected or fed into the water supply pipe 9 inpredetermined quantities. When the port 42 of the valve block 19 isnotclosed by the valve diaphragm 41, a quantity of the chemical solutionon the suction stroke of the pump from right to left may be withdrawnfrom the tank 46 through the pipe 44, a valve block passage 43 and intothe valve chamber 40 from which it passes into the main pump chamber 21through the horizontal valve passage 39. The diaphragm 41 has secured toits right side, as viewed in Fig. 1, a slightly concave annular plate47. This plate 47 is mounted on the diaphragm 41 in registry with thevalve port 42 and serves as a stiffener to insure proper closing contactof the diaphragm 41 against the edgesof the port 42 and the valve block19 when pressure is applied against the right side of the diaphragm 41,as will be more fully explained hereinafter.

The closure plate 48 is also provided with an opening 49 therethrough inwhich a fitting 50 having a pipe 51 connected thereto, is secured, thepurpose of which will be more fully explained hereinafter. The valveblock 19 is also provided with a vertical passage 52 from the lateralpassage 39 and a connecting valve chamber 53 in which a check valve 54is mounted for reciprocation from open to closed position and return inthe conventional manner. The outer end of the check valve chamber 53 isclosed by a fitting 55 threadedly secured therein, this fitting 55having a vertical passage 56 therein connected with a chemical pipe 57which in turn is connected to the main water supply pipe 9. Forconvenience, the pump is shown in inverted position in the diagrammaticview of Fig. 4.

The left body portion 16 of the pump is provided with a lateral passage58 extending therethrough to the chamber 18. In this lateral passage 58there is threadedly secured a fitting 59 having a pipe 60 connectedthereto. The pipe 51 which connects to the valve chamber 46 and the pipe60 which connects to the diaphragm chamber 18 are each connected byproper fittings to a T member 61, asshown particularly in Fig. 4 of thedrawings, which in turn is connected to a short horizontal pipe securedin alignment with a short vertical ejector passage 62 of a hydraulicejector 63. The ejector 63 has secured to its left end a valve body 64having a solenoid controlled valve 66 vertically reciprocable thereinfor opening and closing the passage 67 through the valve body. The valvebody 64 is connected at its left end to a pipe 68 which may be connectedto any source of disposal such as waste. A solenoid device 69 is mountedon the top of the valve body 64 and is connected in an electricalcircuit, also to be more fully described hereinafter, the opening andclosing movement of the valve 66 being effected as this solenoid 69 isenergized or deenergized, respectively.

The ejector 63, which may be operable by the fluid under pressure fromthe main supply pipe 9 or operable by a fluid pressure from any othersource separate and apart therefrom, is provided with a restrictedhorizontal passage 70 extending therethrough and to the right end of theejector there is secured a fitting 71 to which is connected an intakepipe 72 which connects the ejector 63 with the main water supply pipe 9.

When Water under pressure passes through the main water supply pipe 9, aquantity of such water under pressure passes up through the intake pipe72 and into the ejector 63. If the valve 66 on the discharge side of theejector is in closed position as dictated by the electrical controlmeans to be described hereinafter, water pressure is built up in theejector 63, the pipe 65 and in the pipes 51 and 60. The pressure in thepipe 51 builds up a pressure in the valve chamber 40 against the rightside of the valve diaphragm 41 causing it to move to the left so as toclose the port 42 of the horizontal passage 39 of the pump valve block19. Simultaneously, water pressure in the pipe 60 is applied against theleft side of the power diaphragm 13 causing it to move to the rightWithin the chamber 18 which results in movement of the pump rod 26 tothe right on its pumping stroke. As the rod 26 moves to the right on thepumping stroke, the pumping diaphragm 14 is also moved to the right inchamber 21, causing the chemical solution previously withdrawn from thetank 46 and now in the chamber 21, to be forced outwardly from the valveblock 19 through the passages 39 and 52, past the check valve 54, andout through the passage 56 of the fitting 55. The chemical solution isthus pumped into the chemical discharge pipe 57 and into the main watersupply pipe 9. It is to be noted that the valve diaphragm 41 is closedat the beginning of the pumping stroke and prevents leakage of thesolution backwardly into the valve chamber 40 from the pump chamber 21during the pumping stroke. It is to be further understood that the areaof diaphragm 13 is approximately one hundred fifty percent of the areaof diaphragm 14, which insures that fluid can at all times be positivelypumped into the main water line 9 against the pressure therein, thepressure in the pipe 9 being the operating pressure on diaphragm 13.

When a quantity of chemical solution is to be withdrawn from the tank 46and forced into the pumping chamber21 on the suction stroke followingthe pumping stroke, the valve 66 next to the ejector 63 is moved to openposition by the solenoid 69 so that water under pressure passes upwardlythrough the intake pipe 72 and passes through the ejector 63, the valvebody 64 and through the pipe 68 to waste. This ejector action over thevertical passage 62 in the ejector 63'tends to create a vacuum orreduces the pressurein the pipes 5l, 60 and of chemical solution fromthe tank 46. As the diaphragms 13 and 14 commence to move to the left onthe suction stroke, the reduced pressure or vacuum in the pipe 51 causesthe valve diaphragm 41 to move to the right so as .to open the port 420ithe lateral passage 39 of the valve body 19. With the port 42 open, thechemical solution is permitted free passage from the tank 46 into thechamber 21 so that as the pumping diaphragm 14 continues its movement tothe left a quantity of the chemical solution is drawn into the pumpingchamber 21. Following this, the valve 66 is then closed so that pressureis again built up in the pipes 65, 51 and 68 to cause the valvediaphragm 41 to close the valve port 42 and to move the diaphragms 13and 14 to the right for the pumping stroke as above describedywhereuponthe chemical fluid within the pump chamber 21 is forced out into themain water supply pipe 9 through the discharge pipe 57.

The pumping action of the apparatus above described is' made to feed ata rate proportional to the flow of the water in the main water supplypipe 9 by means of a fluid meter, an electric clock or any otherequivalent metering or timing device by which a definite quantity ofadditive may be fed at predetermined intervals or to predeterminedquantities of the main fluid. In the preferred embodiment, a watermeter, indicated generallyby the numeral 73, is shown in Fig. 4, inconjunction with an electrically operated control mechanism which willnow be described. The fluid meter 73 which is interposed in the mainwater line 9, may be of the conventional type and is mechanicallyconnected to a three-way electric switch 74 in such a manner thatwhenever a predetermined volume of fluid has passed through the meter73, the three-way switch 74 will be shifted from one position to theother to complete one circuit or another. As shown somewhatdiagrammatically in Fig. 4, a rotating part or shaft 73a of the meter 73is connected by a chain 76 to a rotatable switch shaft 77 on which issecured a cam 78. The three way switch 74 is provided with contacts 79,88 and 81, the contacts 79 and 80 being adapted to be closed in engagedposition when the cam 78 is in the position shown in Fig. 4 bearingagainst the presser member 82. When the cam '78 has rotated 180 from itsFig. 4 position,

the contacts 79 and 80 will be out of engagement and K contact 88 willthen be in engagement with contact 81.

The contact 80 of the three-way switch 74 is connected to the secondarycoil of a step-down transformer 83 connected to a 115 volt electricoutlet through a main control switch 84 and the secondary coil of thetransformer 83 in which there is produced a reduced operating current ofvolts, is connected to the valve solenoid 69. The contact 79 of thethree-way switch 74 is also connected to the valve solenoid 69 throughengaged contacts 86 and 87 of a second three-way switch indicatedgenerally by the numeral 88. When the foregoing electrical circuit isclosed through the contacts 86 and 87 of the second three-way switch 88and through the contacts 79 and 80 of the three-way switch 74, thesolenoid 69 will be energized to hold the valve 66 in elevated or openposition, thus permitting the water under pressure from the pipe 72 tobe ejected through to waste and thus to cause a reduction in pressure orthe creation of a vacuum in the pipes 65, 51 and for the purposes abovedescribed. 9

The valve 66 may also be held in elevated position when the electriccircuit is closed through the contacts 80 and 81 of the three-way switch74, after the cam 78 thereof has rotated 180 away from its Fig. 4position, and after the contact 87 is in engagement with the contact 85of'the three-way.switch88. Thus thes'olenoid- 6 69 may be energized ineither extreme position of the meter cam 78, the circuits being closedin one position through contacts 79 and of switch 74 and contacts 86 and87 of switch 88 and in the other position through contacts 80 and 81 ofswitch 74 and contacts and 87 of switch 88. The solenoid 69 is thusdeenergized when the cam 78 is moving from one extreme position to theother as above described and during this period of deenergization thevalve 66 is in its down closed position.

The second three-way switch 88 also comprises an electromagnet 89, whichupon being energized attracts a spring urged arm 90 having a downwardlyextending pawl 91 to cause it to move downwardly to actuate a ratchetwheel 92 in a counterclockwise direction. The rachet wheel 92 isoperably connected with a wheel 93 such as by a chain 94 so thatrotation of the wheel 92 will cause rotation of the wheel 93. The arm 90is also provided with a stop finger 9011 which serves to engage therachet 92 and prevent over rotation thereof when the rachet 92 isrotatably advanced by the finger 91. The wheel 93 has a plurality ofradial projections 93:: and recesses 93b on its outer circumferentialedges and is engaged on its upper side by a spring bar 96 having anupwardly directed finger 97 adapted to engage and hold the contact 87 inupward position in engagement with the contact 86. The contact 87 isheld in its upper position when the spring arm 96 is engaged by one ofthe radial projections 93a of the wheel 93 and is permitted to return toits lowered position in engagement with the contact 85 when the recess93b is up so that the circuit is completed through the three-way switch88 in either position.

A depending arm 98 is fixed to the pump rod 26 and the free end of thisarm is adapted to engage a spring pressed plunger 99 of a switch 100 toclose the switch contacts therein when the pump rod 26 reaches itsextreme position at the left. Closing of the contacts of the switch 100completes the electrical circuit to the relay magnet 89 which pulls downthe arm 90 to rotate the wheels 92 and 93. Rotation of the wheel 93moves the radial projection 93a from under the switch spring arm 96 andthe spring arm then engages the Wheel 93 in the recess 93b with theresult that engagement of the contact 87 with the contact 86 is broken,thus opening the circuit to the valve solenoid 69 and causing the valve66 to close. In this closed position of the valve 66, water pressure isbuilt up in the pipes 65, 51 and 60 causing movement of the diaphragms13 and 14 to the right and the consequent pumping of the chemicalsolution from the pump chamber 21 into the main water supply line 9, asabove explained. When the switch contact 87 moves downwardly, it engagesthe contact 85 so that a solenoid energizing circuit will be completedwhen contacts 80 and 81 are in engagement.

As the pump rod 26 moves to the right, the arm 98 moves out of contactwith the switch plunger 99 of the switch 108 thus breaking theengagement between the contacts in the switch and opening the circuit tothe electro-magnet 39 and releasing the arm 90 out of engagement withthe rachet wheel 92. This circuit to the electro-magnet 89 is broken atthe beginning of the pumping stroke and is not reestablished until theend of the return stroke. When the pumping stroke is begun, the cam 78is in its Fig. 4 position with the contacts 79 and 88 of the switch 74still in engagement but the circuit has already been broken as thecontacts 86 and 87 have already broken off engagement. At the end of thepumping stroke, the cam 78 has completed its 189 rotation from its Fig.4 position to permit engagement between the contacts 80 and 81. When theengagement is thus made, the circuit is completed through contacts 85and 87 of switch 88 and contacts 80 and 81 of switch 74 which energizesthe solenoid 69 and raises the valve 66 to open position. Pressure isthus reduced in the pipes:65, 60..a11d- 51 .andthepump starts on itssuction stroke as-above explained.

It is thus apparentz-from'the foregoing description of the details ofstructure and mode of operation of the one embodiment of the presentinvention, that a liquid feedapparatus has been provided which is notonly positive and efficient in operation and capable of feeding liquidto a main water line in direct proportion to the rate of flow of thewaterirrsaid line, but which is'also of simple and relativelyinexpensive construction requiring the outlay of a minimum amount ofmoney for incorporation thereof into small municipal water systems. Thegeneral structural arrangement of the parts is such that the apparatusrequires little or no attention in order to maintain itin efflcientworking condition and its repair and replacement costs are reduced to abare minimum, all springs, stufling boxes and the like of formerstructures which require frequent replacement and repair having beeneliminated. The valve diaphragm 41 is positive in its opening andclosing movements under the positive variations in pressure in the pipe51 and all the disadvantages attendant in the old type of check valvesystemshave been eliminated.

Although there has been illustrated in the drawings and described indetail above one preferred embodiment of the present invention, it is tobe understood that modifications in the details of construction and modeof operation may be made without departing from the spirit and scope ofthe appended claims.

I claim:

1. A liquid feed apparatus for feeding an additive liquid to a secondliquid which comprises a pump adapted to be connected to a source forsaid additive liquid and to said second liquid for withdrawing aquantity of additive liquid from said source on the suction stroke andfor forcing said additive liquid into said second liquid on the pumpingstroke and a valve between said pump and said source of additive liquidadapted to be in closed position during the pumping stroke and in openposition on the suction stroke, and a variable pressure mechanismadapted to be connected to a conduit for liquid under pressure andconnected to said valve and said pump and operable by said liquid underpressure for creating alternately a vacuum to simultaneously eifectopening of the valve and a suction stroke of said pump and a pressure tosimultaneously effect closing of said valve and a pumping stroke of saidpump.

2. A fluid feed apparatus for feeding an additive fluid to a main fluidsupply flowing under pressure in a system having a water flow meterdisposed therein, which comprises a pump adapted to be connected to asource for said additive fluid and to said fluid supply conduit forwithdrawing a quantity of additive fluid from said source on the suctionstroke and for forcing said additive fluid into said fluid supply systemon the pumping stroke, a movable valve between said pump and said sourceof additive fluid, a variable pressure mechanism operable by the mainfluid supply pressure comprising an ejector device connected to saidpump and to said valve and adapted to be connected to said main fluidsupply under pressure through which a quantity of said main fluid supplyunder pressure may flow to discharge and to said pump and valve, a valveadapted to be alternately opened and closed to provide for or preventthe flow of said main fluid through the ejector for creating alternatelyon one side of said pump a vacuum to effect the suction stroke thereofand an increased pressure to effect the pumping stroke thereof and forcreating alternately on one side of said first valve a vacuum to effectmovement of the valve to open position for the suction stroke of thepump and an increascdpressure to effect movement of the valve to closedposition for the pumping stroke, and mechanism for operating said firstvalve adapted to be. operably connected with said meter and controlledthereby in response tothe passageof a predetermined quantity of the mainfluid supply therethrough.

3. Thecombination of a fluid-operated.reciprocating type motor having areciprocating element movable in opposite directions in response to theapplication of vacuum and pressure fluid thereto, a fluid operatedejector, a conduit for-receiving fluid under pressure from a mainconduit and constantly connected to said ejector for constantlysupplying fluid under pressure thereto, means connected to the dischargeof said ejector and adz..-:ed to be opened and closed for providingintermittent flow of fluid from said conduit through said ejector, andmeans responsive to the flow of fluid in said main conduit forrepetitively opening and closing said first-mentioned means, saidejector being connected to said motor and being operable to apply vacuumto said element when said first-mentioned means is opened to permit flowthrough said ejector and to apply pressure fluid to said element whensaid first-mentioned means is closed to prevent flow through saidejector.

4. The combination of a fluid-operated reciprocating type motor having areciprocating element movable in opposite directions in response to theapplication of vacuum and pressure fluid thereto, a fluid operatedejector, a conduit for receiving fluid under pressure from a mainconduit and constantly connected to said ejector for constantlysupplying fluid under pressure thereto, means connected to the dischargeof said ejector and adapted to be opened and closed for providingintermittent flow of fluid from said conduit through said ejector, andmeans responsive to the flow of fluid in said main conduit and thereciprocation of said element for repetitively opening and closing saidfirst-mentioned means, said ejector being connected to said motor andbeing operable to apply vacuum to said element when said first-mentionedmeans is opened to permit flow through said ejector and to applypressure fluid to said element when said first-mentioned means is closedto prevent flow through said ejector.

5. In an additive fluid feed apparatus, in combination, a pump havingintake and discharge passages and including a diaphragm arranged todrive said pump in reciprocation by the alternate application ofpressure and vacuum to one side thereof, a check valve in said dischargepassage, a diaphragm valve in said intage passage adapted to bepositively opened and closed by the alternate appliaction of vacuum andpressure to one side thereof, and a single means for simultaneouslyapplying vacuum to the diaphragms of said pump and said intake valve tosimultaneously effect the suction stroke of said pump and the opening ofsaid diaphragm valve and alternatively simultaneously applying pressureto said diaphragms to simultaneously effect the pumping stroke of saidpump and the closing of said diaphragm valve.

6. Apparatus for feeding additive liquid to a main under pressurecomprising a diaphragm pump having intake and discharge passages adaptedto be connected, respectively, with a source of additive liquid and withsaid main; a check valve in said discharge passage; a diaphragm valve insaid intake passage adapted to be positively opened and closed by thealternate application of vacuum and pressure to one side thereof; and anhydraulic system for driving said diaphragm pump and operating saiddiaphragm valve comprising an ejector having an inlet adapted to becontinuously connected to a source of liquid under pressure, saidejector being connected to said diaphragm pump and said diaphragm valve;a valve in the discharge of said ejector to control the flow of liquidthrough said ejector; and means for opening and closing said ejectordischarge valve to alternatively apply vacuum and pressuresimultaneously to said diaphragm pump and said diaphragm valve tooperate said pump and said diaphragm .valve.

7. Apparatus for feeding additive liquid to a main under pressurecomprising a diaphragm pump having intake and discharge passages adaptedto be connected, respectively, with a source of additive liquid and withsaid main; a check valve in said discharge passage; a diaphragm valve insaid intake passage adapted to be positively opened and closed by thealternate application of vacuum and pressure to one side thereof; adiaphragm motor for driving said diaphragm pump; an hydraulic system fordriving said diaphragm motor and operating said diaphragm valvecomprising an ejector having an inlet adapted to be continuouslyconnected to a source of liquid under pressure, said ejector beingconnected to said diaphragm motor and said diaphragm valve; a valve inthe discharge of said ejector to control the flow of liquid through saidejector; and means for opening and closing said ejector discharge valveto alternatively apply vacuum and pressure simultaneously to saiddiaphragm motor and said diaphragm valve to operate said pump and saiddiaphragm valve.

8. Apparatus in accordance with claim 7 wherein the ejector dischargevalve is a solenoid valve and the means for opening and closing saidsolenoid valve comprises an electromechanical system including a controldevice responsive to the volume of flow of liquid in the main.

9. Apparatus in accordance with claim 7 wherein the ejector dischargevalve is a normally closed solenoid valve and the means for opening andclosing said solenoid valve comprises an electro-mechanical systemincluding a flow 10 meter disposed in the main and arranged to initiateaction to open said ejector discharge valve to effect the suction strokeof the pump and means associated with the pump operative to initiateaction to re-close said ejector discharge valve at the end of thesuction stroke to effect the discharge stroke of said pump.

References Cited in the file of this patent UNITED STATES PATENYIS298,875 Millard May 20, 1884 637,260 Hall Nov. 21, 1899 1,875,022Krueger Aug. 30, 1932 1,991,235 True et al. Feb. 12, 1935 2,080,872Paterson May 18, 1937 2,211,753 Leopold Aug. 20, 1940 2,218,773 SparlingOct. 22, 1940 2,229,038 Booth Jan. 21, 1941 2,238,747 Ornstein Apr. 15,1941 2,289,332 Booth July 14, 1942 2,289,333 Booth July 14, 19422,310,459 Potter Feb. 9, 1943 2,391,703 Hughes Dec. 25, 1945 2,417,994Sheets Mar. 28, 1947 2,529,028 Landon Nov. 7, 1950 FOREIGN PATENTS370,842 Great Britain Apr. 14, 1923

1. A LIQUID FEED APPARATUS FOR FEEDING AN ADDITIVE LIQUID TO A SECONDLIQUID WHICH COMPRISES A PUMP ADAPTED TO BE CONNECTED TO A SOURCE FORSAID ADDITIVE LIQUID AND TO SAID SECOND LIQUID FOR WITHDRAWING AQUANTITY OF ADDITIVE LIQUID FROM SAID SOURCE ON THE SUCTION STROKE ANDFOR FORCING SAID ADDITIVE LIQUID INTO SAID SECOND LIQUID ON THE PUMPINGSTROKE AND A VALVE BETWEEN SAID PUMP AND SAID SOURCE OF ADDITIVE LIQUIDADAPTED TO BE IN CLOSED POSITION DURING THE PUMPING STROKE AND IN OPENPOSITION ON THE SUCTION STROKE, AND A VARIABLE PRESSURE MECHANISMADAPTED TO BE CONNECTED TO A CONDUIT FOR LIQUID UNDER